A day after working out for the Knicks, Kansas center Jeff Withey showed his wares for the Brooklyn Nets – including his vaunted defense and even a newfound jumper he feels could make him the perfect backup for old friend Brook Lopez.

“I think I’d fit in pretty well. I know Brook pretty well. We played on the same AAU team; I was a freshman he was a senior. I know him and his brother really well,’’ said Withey, whose Horizon High School won a California Division IV semi over a San Joaquian Memorial team featuring both Brook and Robin Lopez.

“We played them in the state championship. I know him and Tyshawn (Taylor) is another Kansas guy. I feel like I’d fit in very well. They need that backup center and I feel that’s something I could provide my first year. I could learn a lot from these coaches and Brook.’’

Several mock drafts at one point predicted the Nets would take Withey 22nd overall, although now DraftExpress has him going 29th and NBAdraft.net has him slipping to Sacramento in the second round at No. 36 overall.

“Jeff Withey (impressed with) his size, his length, the ability to make an impact at the rim,’’ said director of player personnel Gregg Polinsky, who oversaw a workout with a total of six players today at the Nets’ training facility.

“I thought he was good, (I was) not disappointed at all. He stepped out; we had him shoot some 3s at the end, because we think that’s one of the things he can do, be a pick-and-pop 5. Those are hard to find. Obviously he gives you a presence at the rim defensively, a good solid defensive rebounder in college and he comes from a place in Kansas where it’s not done any better.’’

Withey followed up a junior season averaging 3.6 blocks with a season campaign averaging 3.9, setting the Big 12 career record (311) and being named co-Defensive Player of the Year by the National Association of Basketball Coaches. But at 6-11 and just 235 lbs., he’s not the bulkiest center in the draft and knows he’ll have to add a jumper.

“That’s what I’ve been working on is my offensive game: My shot and my 15-foot range. I felt very happy with it; I’m starting to get better offensively,’’ said Withey. “Defensively it’s tough to show people what you’ve got; I’m a shot-blocker, and it’s hard to do that in a one-on-one situation. I get a lot of my blocks off helping.

“I know that I’m not a very big strong guy. I’m not going to be taking people in the post and backing them down, so that’s why I started working on my jump shot. I’ve had it; it’s just as Kansas we don’t do that. We play a lot of high-low offense where you’re going into the paint, pick-and-rolls, stuff like that.

“But I know if I want to be a good player in the NBA I need to make that shot, because my body just won’t back people down and score. So I’m putting all my effort into getting that shot down, and so far I’m liking what’s come out of it.’’

Cal shooting guard Allen Crabbe, another anticipated first-round pick, stopped just ten minutes into the workout with a foot injury. He said it never bothered him at Cal, but cropped up near the end of Monday’s workout with the Knicks. He pushed through it then, but when it hurt so early into today’s workout, he had to use precaution lest he suffer something more severe.

“It did towards end of the workout, but by the time it was almost over so I just pushed through it,’’ said Crabbe, adding that Tuesday “It felt like it was going to break at one point, so I just said I’m going to shut it down.’’

Both point guard Deron Williams and GM Billy King were on hand, but neither addressed the media or answered questions regarding the Nets’ coaching search.